The Effect of Root Coating with Titanium on Prevention of Root Resorption in Avulsed Teeth; An Animal Study

Introduction: Tooth avulsion is a real dental emergency. If immediate replantation is not performed, the avulsed tooth may be lost due to inflammatory or replacement resorption. This animal study aimed to evaluate the bone response to the titanium coating of the root surface as an artificial barrier, and prevention of resorption of avulsed teeth. Methods and Materials: This experimental study was conducted on four male dogs. The dogs were randomly divided into two groups for assessment at two and eight weeks. Four teeth were extracted in each animal. The root surfaces of the test group were coated with a titanium layer using the Electron Beam Deposition system. After 24 h, replantation of the teeth was performed. Two animals were sacrificed after two weeks and the remaining dogs were killed after eight weeks. The presence of inflammation, inflammatory resorption, replacement resorption, periodontal regeneration, periapical granuloma and ankylosis were evaluated through histological analyses. Results: Inflammatory root resorption was not present in any tooth except one tooth in the coated group after eight weeks. Replacement resorption was noted just in three of the non-coated teeth after two weeks and two teeth after eight weeks. The McNemar's test revealed that the frequency of replacement resorption in the non-coated group was significantly higher than the coated group (P=0.031). Conclusion: Based on the results of this study, it seems that coating the root surfaces of avulsed teeth with titanium may control the replacement root resorption.Keywords: Avulsion; Root Resorption; Titanium Coatin

Epidemiological characteristics of coronavirus disease 2019 (COVID-19) patients in IRAN: A single center study.

BackgroundAn outbreak of COVID-19 in Iran has spread throughout the country. Identifying the epidemiological characteristics of this disease will help to make appropriate decisions and thus control the epidemic. The aim of this study was characterization of the epidemiological features of COVID-19 in Iran.MethodsIn this retrospective study, data related to the epidemiological characteristics of COVID-19 patients admitted to Baqiyatallah Hospital in Tehran, Iran, from 19 February 2020 to 15 April 2020 have been analyzed and reported. Patient characteristics including age, gender and underlying diseases were investigated. Data were collected through patient records. Sex ratio, Case Fatality Rate (CFR) and daily trend of cases were also determined. A multiple logistic regression analysis was also performed to assess affecting factors on mortality.ResultsFrom February 19, 2020 to April 15, 2020, 12870 patients referred to the hospital emergency department, of which 2968 were hospitalized with COVID-19 diagnosis. The majority of cases were in the age group of 50 to 60 years of old. The male-to-female ratio was 1.93:1. A total of 239 deaths occurred among all cases for an overall CFR of 1.85% based on the total number of patients (both outpatient and inpatient) and 8.06% among hospitalized patients. Out of all patients 10.89% had comorbidity. Diabetes, chronic respiratory diseases, hypertension, cardiovascular diseases, chronic Kidney diseases and cancer were the most common comorbidities with 3.81, 2.02 , 1.99 , 1.25, 0.60 and 0.57 %, respectively. Male gender (OR=1.45, 95% CI: 1.08-1.96), older age (OR=1.05, 95% CI: 1.04-1.06) and having underlying diseases (OR=1.53, 95% CI: 1.04-2.24) were significantly associated with mortality.ConclusionsThe results of this study showed that Male gender, older age and having comorbidities were significantly associated with the risk of death among COVID-19 patients. It is important to pay special attention to male elderly patients with underlying diseases

Density-Dependence of Surface Transport in Tellurium-Enriched Nanograined Bulk Bi2Te3

Three-dimensional topological insulators (3D TI) exhibit conventional parabolic bulk bands and protected Dirac surface states. A thorough investigation of the different transport channels provided by the bulk and surface carriers using macroscopic samples may provide a path toward accessing superior surface transport properties. Bi2Te3 materials make promising 3D TI models; however, due to their complicated defect chemistry, these materials have a high number of charge carriers in the bulk that dominate the transport, even as nanograined structures. To partially control the bulk charge carrier density, herein the synthesis of Te-enriched Bi2Te3 nanoparticles is reported. The resulting nanoparticles are compacted into nanograined pellets of varying porosity to tailor the surface-to-volume ratio, thereby emphasizing the surface transport channels. The nanograined pellets are characterized by a combination of resistivity, Hall- and magneto-conductance measurements together with (THz) time-domain reflectivity measurements. Using the Hikami-Larkin-Nagaoka (HLN) model, a characteristic coherence length of ≈200 nm is reported that is considerably larger than the diameter of the nanograins. The different contributions from the bulk and surface carriers are disentangled by THz spectroscopy, thus emphasizing the dominant role of the surface carriers. The results strongly suggest that the surface transport carriers have overcome the hindrance imposed by nanoparticle boundaries

A Deep Insight Into CAR-T Cell Therapy in Non-Hodgkin Lymphoma: Application, Opportunities, and Future Directions

Non-Hodgkin’s lymphoma (NHL) is a cancer that starts in the lymphatic system. In NHL, the important part of the immune system, a type of white blood cells called lymphocytes become cancerous. NHL subtypes include marginal zone lymphoma, small lymphocytic lymphoma, follicular lymphoma (FL), and lymphoplasmacytic lymphoma. The disease can emerge in either aggressive or indolent form. 5-year survival duration after diagnosis is poor among patients with aggressive/relapsing form of NHL. Therefore, it is necessary to understand the molecular mechanisms of pathogenesis involved in NHL establishment and progression. In the next step, we can develop innovative therapies for NHL based on our knowledge in signaling pathways, surface antigens, and tumor milieu of NHL. In the recent few decades, several treatment solutions of NHL mainly based on targeted/directed therapies have been evaluated. These approaches include B-cell receptor (BCR) signaling inhibitors, immunomodulatory agents, monoclonal antibodies (mAbs), epigenetic modulators, Bcl-2 inhibitors, checkpoint inhibitors, and T-cell therapy. In recent years, methods based on T cell immunotherapy have been considered as a novel promising anti-cancer strategy in the treatment of various types of cancers, and particularly in blood cancers. These methods could significantly increase the capacity of the immune system to induce durable anti-cancer responses in patients with chemotherapy-resistant lymphoma. One of the promising therapy methods involved in the triumph of immunotherapy is the chimeric antigen receptor (CAR) T cells with dramatically improved killing activity against tumor cells. The CAR-T cell-based anti-cancer therapy targeting a pan–B-cell marker, CD19 is recently approved by the US Food and Drug Administration (FDA) for the treatment of chemotherapy-resistant B-cell NHL. In this review, we will discuss the structure, molecular mechanisms, results of clinical trials, and the toxicity of CAR-T cell-based therapies. Also, we will criticize the clinical aspects, the treatment considerations, and the challenges and possible drawbacks of the application of CAR-T cells in the treatment of NHL

Mapping local patterns of childhood overweight and wasting in low- and middle-income countries between 2000 and 2017

A double burden of malnutrition occurs when individuals, household members or communities experience both undernutrition and overweight. Here, we show geospatial estimates of overweight and wasting prevalence among children under 5 years of age in 105 low- and middle-income countries (LMICs) from 2000 to 2017 and aggregate these to policy-relevant administrative units. Wasting decreased overall across LMICs between 2000 and 2017, from 8.4% (62.3 (55.1–70.8) million) to 6.4% (58.3 (47.6–70.7) million), but is predicted to remain above the World Health Organization’s Global Nutrition Target of <5% in over half of LMICs by 2025. Prevalence of overweight increased from 5.2% (30 (22.8–38.5) million) in 2000 to 6.0% (55.5 (44.8–67.9) million) children aged under 5 years in 2017. Areas most affected by double burden of malnutrition were located in Indonesia, Thailand, southeastern China, Botswana, Cameroon and central Nigeria. Our estimates provide a new perspective to researchers, policy makers and public health agencies in their efforts to address this global childhood syndemic

Thermoelectric and electrical transport properties of Bi2Te3 compacted nanoparticles bulk material

Izadi S. Thermoelectric and electrical transport properties of Bi2Te3 compacted nanoparticles bulk material. Bielefeld: Universität Bielefeld; 2021.Three-dimensional (3D) topological insulators (TI) host surface carriers with extremely high mobility. However, their transport properties are typically dominated by bulk carriers that outnumber the surface carriers by orders of magnitude. We herein present a strategy to overcome the problem of bulk carrier domination by using 3D TI nanoparticles, which were compacted by hot-pressing to macroscopic nanograined bulk samples. Bi2Te3 nanoparticles well known for their excellent thermoelectric and 3D TI properties serve as our model system. As key enabler for this approach, we applied a specific synthesis that creates nanoparticles with a low level of impurities and surface contamination. The compacted nanograined bulk contains a high number of interfaces and grain boundaries. Here we show that these samples exhibit metallic-like electrical transport properties and a distinct weak antilocalization. A downwards trend in the electrical resistivity at temperatures below 5 K was attributed to an increase in the coherence length by applying the Hikami-Larkin-Nagaoka model. THz time-domain spectroscopy revealed a dominance of the surface transport at low frequencies with a mobility of above 〖10〗^3 cm^2 V^(-1) s^(-1) even at room temperature. These findings clearly demonstrate that nanograined bulk Bi2Te3 features surface carrier properties that are of importance for technical applications

Epidemiology of musculoskeletal disorders among iranian adults: results from a non-communicable disease cohort study

Abstract Background Persistent pain and reduced mobility and dexterity are the typical characteristics of Musculoskeletal disorders (MSDs). We aimed to determine the prevalence of back and joint pain, back, and joint stiffness, arthritis, and osteoporosis among adults and their distribution according to sociodemographic characteristics and comorbidities. Methods This cross-sectional study was conducted on 9,520 participants aged 35–65 years from baseline data of the Ravansar Non-Communicable Disease (RaNCD) cohort study, in the west of Iran. MSDs were evaluated by the RaNCD cohort study physician using a standard questionnaire. Binary logistic regression was used to determine associations and reported by odds ratios (OR) and 95% confidence intervals (CI). Results The MSDs in women were significantly more than in men (59.06% vs. 40.94%, P < 0.001). Skeletal muscle mass (SMM) was significantly lower in subjects with MSDs, and waist circumference (WC) and visceral fat area (VFA) were higher than in the non-MSDs (P < 0.001). MSDs were significantly more common in urban men and women (OR = 1.33; 95% CI: 1.14–1.50 and OR = 1.59; 95% CI: 1.39–1.82, respectively). Obesity increased the odds of MSDs in women (OR = 1.57; 95% CI: 1.33–1.84), whereas there was no association between BMI and MSDs in men. Men with high socioeconomic status (SES) had lower odds of MSDs than men with weak SES (OR = 0.77; 95% CI: 0.64–0.92). Conclusion The MSDs were more prevalent among older people, women, obese people and urban dwellers. Lifestyle modification, especially weight loss may be helpful in reducing and controlling MSDs

Interface-Dominated Topological Transport in Nanograined Bulk Bi2 Te3

3D topological insulators (TI) host surface carriers with extremely high mobility. However, their transport properties are typically dominated by bulk carriers that outnumber the surface carriers by orders of magnitude. A strategy is herein presented to overcome the problem of bulk carrier domination by using 3D TI nanoparticles, which are compacted by hot pressing to macroscopic nanograined bulk samples. Bi2Te3 nanoparticles well known for their excellent thermoelectric and 3D TI properties serve as the model system. As key enabler for this approach, a specific synthesis is applied that creates nanoparticles with a low level of impurities and surface contamination. The compacted nanograined bulk contains a high number of interfaces and grain boundaries. Here it is shown that these samples exhibit metallic-like electrical transport properties and a distinct weak antilocalization. A downward trend in the electrical resistivity at temperatures below 5 K is attributed to an increase in the coherence length by applying the Hikami–Larkin–Nagaoka model. THz time-domain spectroscopy reveals a dominance of the surface transport at low frequencies with a mobility of above 103 cm2 V−1 s−1 even at room temperature. These findings clearly demonstrate that nanograined bulk Bi2Te3 features surface carrier properties that are of importance for technical applications

Density-Dependence of Surface Transport in Tellurium-Enriched Nanograined Bulk Bi2 Te3

Izadi S, Bhattacharya A, Salloum S, et al. Density-Dependence of Surface Transport in Tellurium-Enriched Nanograined Bulk Bi2 Te3. Small . 2023: e2204850.Three-dimensional topological insulators (3D TI) exhibit conventional parabolic bulk bands and protected Dirac surface states. A thorough investigation of the different transport channels provided by the bulk and surface carriers using macroscopic samples may provide a path toward accessing superior surface transport properties. Bi2 Te3 materials make promising 3D TI models; however, due to their complicated defect chemistry, these materials have a high number of charge carriers in the bulk that dominate the transport, even as nanograined structures. To partially control the bulk charge carrier density, herein the synthesis of Te-enriched Bi2 Te3 nanoparticles is reported. The resulting nanoparticles are compacted into nanograined pellets of varying porosity to tailor the surface-to-volume ratio, thereby emphasizing the surface transport channels. The nanograined pellets are characterized by a combination of resistivity, Hall- and magneto-conductance measurements together with (THz) time-domain reflectivity measurements. Using the Hikami-Larkin-Nagaoka (HLN) model, a characteristic coherence length of 200 nm is reported that is considerably larger than the diameter of the nanograins. The different contributions from the bulk and surface carriers are disentangled by THz spectroscopy, thus emphasizing the dominant role of the surface carriers. The results strongly suggest that the surface transport carriers have overcome the hindrance imposed by nanoparticle boundaries. © 2023 The Authors. Small published by Wiley-VCH GmbH

Influence of Nanoparticle Processing on the Thermoelectric Properties of (BixSb1-X)(2)Te-3 Ternary Alloys

Salloum S, Bendt G, Heidelmann M, et al. Influence of Nanoparticle Processing on the Thermoelectric Properties of (BixSb1-X)(2)Te-3 Ternary Alloys. ChemistryOpen . 2021;10(2):189-198.The synthesis of phase-pure ternary solutions of tetradymite-type materials (BixSb1-x)(2)Te-3 (x=0.25; 0.50; 0.75) in an ionic liquid approach has been carried out. The nanoparticles are characterized by means of energy-dispersive X-ray spectroscopy (EDX), powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), and transmission electron microscopy. In addition, the role of different processing approaches on the thermoelectric properties - Seebeck coefficient as well as electrical and thermal conductivity - is demonstrated